[FFmpeg-devel] Warnings (Was: Re: [PATCH 1/2] avutil/attributes: extend av_uninit to clang)

[Moritz Barsnick]

On Wed, Oct 07, 2015 at 23:35:08 +0200, Moritz Barsnick wrote:
> On Wed, Oct 07, 2015 at 16:07:53 -0400, Ronald S. Bultje wrote:
> > > BTW, are the "remaining" (meaning: more than from gcc) warnings emitted
> > > by the Intel C(++) Compiler redundant or false? The icc configuration
> > > should then probably silence them.
> > 
> > I doubt anyone has ever investigated them...
> 
> configure creates a quite explicit list of warning suppressions for icc
> already. Somebody did investigate at one point. My icc is a bit old
> (14.0.3.174 is the newest I have a license for), but I can take a stab
> sometime, or ask here what the point of the warnings could be, if noone
> minds.

I don't even need to run my icc, fate has logs from icc builds with
plenty of versions, such as:
http://fate.ffmpeg.org/log.cgi?time=20151012035217&log=compile&slot=x86_64-linux-gnu-icc-2013_sp1.2.144

Apart from the intentional "declared deprecated" warnings:
- quite a few "deprecated conversion of string literal to char* (should
  be const char*)", which are classified as warning #3179 and could be
  suppressed (I think I once figured out why they are there - but can't
  remember);
- only two other warnings:
  - /home/fate/fate/slots/x86_64-linux-gnu-icc-2013_sp1.2.144/src/libavcodec/pngenc.c(273): warning #2332: a value of type "const uint8_t={unsigned char} *" cannot be assigned to an entity of type "Bytef={Byte={unsigned char}} *" (dropping qualifiers)
          s->zstream.next_in  = data;
                              ^
  - /home/fate/fate/slots/x86_64-linux-gnu-icc-2013_sp1.2.144/src/libavcodec/tscc.c(82): warning #2332: a value of type "const uint8_t={unsigned char} *" cannot be assigned to an entity of type "Bytef={Byte={unsigned char}} *" (dropping qualifiers)
          c->zstream.next_in   = buf;
                               ^
- and these presumably new and as-yet unresolved unused return value warnings:
  - /home/fate/fate/slots/x86_64-linux-gnu-icc-2013_sp1.2.144/src/ffmpeg.c(220): warning #2218: result of call is not used
          av_buffersrc_add_frame_flags(ist->filters[i]->filter, frame,
          ^

    /home/fate/fate/slots/x86_64-linux-gnu-icc-2013_sp1.2.144/src/ffmpeg.c(295): warning #2218: result of call is not used
          av_buffersrc_add_frame(ist->filters[i]->filter, NULL);
          ^

So, nothing much in special. May need a short check.
Moritz